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Rearranging powers (Logs, I think?) Watch

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    I've got the question:
    The gas in a cylinder has an initial volume (V) of 0.01m^3 and a pressure (P) of 250kN/m^2. The gas is then compressed by the piston to a pressure of 800kN/m^2 according to the law P(V)^1.2 = C where C is a constant. Find the final volume giving your answer correct to five sig fig.

    So I know that 250000 x 0.01^1.2 = 995.27

    And so then 800000 x V^1.2 = 995.27
    So V^1.2 = 0.001244

    But now I'm stuck.
    I tried using logs, but that just left me at a dead end. Anyone able to help with this?
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    I still don't know how to rearrange that. As I'm left with Log (base 1.2) V. I now know the answer via trial and error, but I can't rearrange the logs.
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    (Original post by IREngineerer)
    I've got the question:
    The gas in a cylinder has an initial volume (V) of 0.01m^3 and a pressure (P) of 250kN/m^2. The gas is then compressed by the piston to a pressure of 800kN/m^2 according to the law P(V)^1.2 = C where C is a constant. Find the final volume giving your answer correct to five sig fig.

    So I know that 250000 x 0.01^1.2 = 995.27

    And so then 800000 x V^1.2 = 995.27
    So V^1.2 = 0.001244

    But now I'm stuck.
    I tried using logs, but that just left me at a dead end. Anyone able to help with this?
    You could think of it like this:

    V6/5 = 0.001244
    V = (0.001244)5/6
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    Yes actually raise both sides to the power 5/6.
 
 
 
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